This is a working overview of epithalamin, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-03-21. Anything still debated is marked as such rather than presented as settled.
Chemically, the molecule consists of four amino acid residues joined by three peptide bonds, with a free N-terminal amino group and a free C-terminal carboxyl group. Its molecular formula is C14H22N4O9, and its monoisotopic mass is approximately 390 daltons. The acidic glutamate and aspartate side chains give the peptide a net negative charge near neutral pH, a property that shapes its chromatographic behaviour and solubility profile. No disulfide bridges or other post-translational modifications are present, so the primary sequence alone defines the structure.
Most experimental work has been carried out in cell culture and animal models. Several reports describe changes in telomerase activity and proliferation in cultured cells, while rodent studies have examined lifespan, melatonin rhythm and reproductive endpoints. Human data remain limited, and much of the published clinical material consists of small trials with incomplete reporting of methods and controls. Whether the cell and animal findings translate into measurable effects in people is an open question, and the mechanistic basis of the reported telomerase changes is not fully established.
Epitalon is a synthetic tetrapeptide whose four residues are alanine, glutamate, aspartate and glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9 and its monoisotopic mass is near 390.35 daltons. The peptide carries two acidic side chains, so it is neutral to negatively charged in most aqueous buffers. Published reference summaries usually list it under both spellings, epitalon and epithalon, and treat the two names as the same material.
The compound is generally described as a synthetic analogue of a fragment isolated from a pineal gland extract. Researchers associated with the Saint Petersburg Institute of Bioregulation and Gerontology introduced it during the 1980s and 1990s while studying short peptides from animal tissue. The original extract, called epithalamin, is a heterogeneous mixture, whereas epitalon is a single defined sequence. That distinction matters because findings reported for the extract are not automatically findings about the pure tetrapeptide, and claims about broader biological effects remain a separate question from the chemical identity described here.
Residue composition is the property that most cleanly separates verified material from mislabelled samples. Alanine, glutamate, aspartate and glycine appear in that order from the N-terminus, and the two acidic residues sit in the middle of the chain. Because the peptide is short, it can be produced by solid-phase synthesis and characterised by mass spectrometry without ambiguity. Any reported sample whose measured mass departs substantially from 390 daltons is a different compound or a degraded mixture rather than epitalon.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Linear tetrapeptide | Four residues joined by three peptide bonds |
| Sequence | Ala-Glu-Asp-Gly | Commonly abbreviated AEDG |
| Molecular formula | C14H22N4O9 | Free acid form |
| Monoisotopic mass | Approximately 390 Da | Matches values reported from mass spectrometry |
| Net charge near neutral pH | Negative | Contributed by glutamate and aspartate side chains |
Epitalon is the common name for a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, usually abbreviated AEDG. All four residues are proteinogenic amino acids, and the free peptide has a calculated mass near 390 grams per mole. Because the chain is short and carries no modifications, it is assembled readily by solid-phase synthesis and is distributed mainly as a freeze-dried solid for laboratory work. Catalogue listings use the spellings epitalon, epithalone, and simply AEDG, and the three refer to the same sequence.
The compound is generally presented as a synthetic fragment of epithalamin, a pineal gland extract investigated in the former Soviet Union from the 1970s onward. Vladimir Khavinson and colleagues in Saint Petersburg developed short peptides modelled on such extracts, and epitalon became the most widely cited of those sequences. Most primary reports appeared in Russian-language journals or in proceedings with limited international circulation. Independent replication in laboratories outside that network remains sparse, and much repeated secondary material traces back to a small number of originating groups.
Laboratory work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
Epitalon is a synthetic four-amino-acid peptide with the sequence alanine-glutamate-aspartate-glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9, and its calculated molar mass is approximately 390.35 grams per mole. The compound is a short fragment related to a peptide fraction isolated from bovine pineal gland extracts, and it is normally supplied as a lyophilised powder intended for laboratory research. It is not a registered pharmaceutical product in most countries.
The peptide emerged from research carried out in Saint Petersburg from the late 1980s onward, where investigators searched for shorter active fragments of a pineal preparation known as epithalamin. The name epitalon was chosen to reflect that parent extract. Early reports described effects on neuroendocrine markers and on the lifespan of laboratory animals. Much of that work appeared in Russian-language journals, with English translations following later, which affects how readily the original protocols can be assessed by outside groups.
=== POMC === POMC produced from the melanotropes of the pars intermedia is cleaved into adrenocorticotropic hormone (ACTH) and β-lipotropin (β-LPH). The majority of ACTH is then cleaved into α-MSH and corticotropin-like intermediate peptide (CLIP). CLIP is thought to have an influence on subsequent insulin resistance that can be seen in PPID horses. ACTH is also produced by corticotropes in the pars distalis of the equine pituitary. In a normal horse, this accounts for the majority of ACTH production. ACTH produced by the pars distalis is subject to negative feedback in a normal horse, so high cortisol levels reduce ACTH production by the pituitary, subsequently reducing cortisol levels. In a horse with PPID, ACTH levels are high as a result of pars intermedia production, but it is not subject to negative feedback regulation. Despite the high levels of ACTH, cortisol levels vary, and are sometimes lower than normal. Additionally, hyperplasia of the adrenal cortex is infrequent. The role of ACTH is, therefore, still poorly understood.
=== EC 1.14.99 Miscellaneous === EC 1.14.99.1: prostaglandin-endoperoxide synthase EC 1.14.99.2: kynurenine 7,8-hydroxylase EC 1.14.99.3: Now EC 1.14.14.18, heme oxygenase (biliverdin-producing) EC 1.14.99.4: progesterone monooxygenase EC 1.14.99.5: Now EC 1.14.19.1, stearoyl-CoA 9-desaturase EC 1.14.99.6: Now EC 1.14.19.2, acyl-[acyl-carrier-protein] desaturase EC 1.14.99.7: Transferred to EC 1.14.13.132, squalene monooxygenase EC 1.14.99.8: Now included with EC 1.14.14.1 unspecific monooxygenase EC 1.14.99.9: Now classified as EC 1.14.14.19, steroid 17α-monooxygenase EC 1.14.99.10: Now EC 1.14.14.16, steroid 21-monooxygenase EC 1.14.99.11: estradiol 6β-monooxygenase EC 1.14.99.12: 4-androstene-3,17-dione monooxygenase EC 1.14.99.13: Now EC 1.14.13.23, 3-hydroxybenzoate 4-monooxygenase EC 1.14.99.14: Now EC 1.14.14.197, progesterone 11α-monooxygenase EC 1.14.99.15: 4-methoxybenzoate monooxygenase (O-demethylating) EC 1.14.99.16: Now EC 1.14.13.72, methylsterol monooxygenase EC 1.14.99.17: Now EC 1.14.16.5, glyceryl-ether monooxygenase EC 1.14.99.18: deleted EC 1.14.99.19: Now classified as EC 1.14.19.77, plasmanylethanolamine desaturase EC 1.14.99.20: phylloquinone monooxygenase (2,3-epoxidizing) EC 1.14.99.21: Latia-luciferin monooxygenase (demethylating) EC 1.14.99.22: ecdysone 20-monooxygenase EC 1.14.99.23: 3-hydroxybenzoate 2-monooxygenase EC 1.14.99.24: steroid 9α-monooxygenase EC 1.14.99.25: Now EC 1.14.19.3, linoleoyl-CoA desaturase EC 1.14.99.26: 2-hydroxypyridine 5-monooxygenase EC 1.14.99.27: Now classified as EC 1.17.3.4, juglone 3-monooxygenase EC 1.14.99.28: Now EC 1.14.14.84, linalool 8-monooxygenase EC 1.14.99.29: deoxyhypusine monooxygenase EC 1.14.99.30: Now EC 1.3.5.6, 9,9′-dicis-ζ-carotene desaturase. EC 1.14.99.31: Now classified as EC 1.14.19.24, myristoyl-CoA 11-(E) desaturase EC 1.14.99.32: Now classified as EC 1.14.19.5, acyl-CoA 11-(Z)-desaturase EC 1.14.99.33: Now EC 1.14.19.39, acyl-lipid Δ12-acetylenase EC 1.14.99.34: monoprenyl isoflavone epoxidase EC 1.14.99.35: thiophene-2-carbonyl-CoA monooxygenase EC 1.14.99.36: Now classified as EC 1.13.11.63, β-carotene 15,15′-dioxygenase EC 1.14.99.37: Now EC 1.14.14.176, taxadiene 5α-hydroxylase EC 1.14.99.38: cholesterol 25-hydroxylase EC 1.14.99.39: ammonia monooxygenase EC 1.14.99.40: Now EC 1.13.11.79, 5,6-dimethylbenzimidazole synthase EC 1.14.99.41: Now EC 1.13.11.75, all-trans-8′-apo-β-carotenal 15,15′-oxygenase EC 1.14.99.42: Now EC 1.13.11.84, crocetin dialdehyde synthase EC 1.14.99.43: Now EC 1.14.14.134, β-amyrin 24-hydroxylase EC 1.14.99.44: diapolycopene oxygenase EC 1.14.99.45: Now EC 1.14.14.158, carotene ε-monooxygenase EC 1.14.99.46: pyrimidine oxygenase EC 1.14.99.47: (+)-larreatricin hydroxylase EC 1.14.99.48: heme oxygenase (staphylobilin-producing) EC 1.14.99.49: Now EC 1.14.15.31, 2-hydroxy-5-methyl-1-naphthoate 7-hydroxylase EC 1.14.99.50: γ-glutamyl hercynylcysteine S-oxide synthase EC 1.14.99.51: hercynylcysteine S-oxide synthase EC 1.14.99.52: L-cysteinyl-L-histidinylsulfoxide synthase EC 1.14.99.53: lytic chitin monooxygenase EC 1.14.99.54: lytic cellulose monooxygenase (C1-hydroxylating) EC 1.14.99.55: lytic starch monooxygenase EC 1.14.99.56: lytic cellulose monooxygenase (C4-dehydrogenating) EC 1.14.99.57: heme oxygenase (mycobilin-producing) EC 1.14.99.58: heme oxygenase (biliverdin-IX-β and δ-forming) EC 1.14.99.59: tryptamine 4-monooxygenase EC 1.14.99.60: 3-demethoxyubiquinol 3-hydroxylase EC 1.14.99.61: cyclooctat-9-en-7-ol 5-monooxygenase EC 1.14.99.62: cyclooctatin synthase EC 1.14.99.63: β-carotene 4-ketolase EC 1.14.99.64: zeaxanthin 4-ketolase EC 1.14.99.65: 4-amino-L-phenylalanyl-[CmlP-peptidyl-carrier-protein] 3-hydroxylase EC 1.14.99.66: [histone H3]-N6,N6-dimethyl-L-lysine4 FAD-dependent demethylase EC 1.14.99.67: α-N-dichloroacetyl-p-aminophenylserinol N-oxygenase EC 1.14.99.68: 4-aminobenzoate N-oxygenase EC 1.14.99.69: tRNA 2-(methylsulfanyl)-N6-isopentenyladenosine37 hydroxylase
Selenium, in the form of organoselenium compounds, is an essential micronutrient whose absence from the diet causes cardiac muscle and skeletal dysfunction. Organoselenium compounds are required for cellular defense against oxidative damage and for the correct functioning of the immune system. They may also play a role in prevention of premature aging and cancer. The source of Se used in biosynthesis is selenophosphate. Glutathione oxidase is an enzyme with a selenol at its active site. Organoselenium compounds have been found in higher plants. For example, upon analysis of garlic using the technique of high-performance liquid chromatography combined with inductively coupled plasma mass spectrometry (HPLC-ICP-MS), it was found that γ-glutamyl-Se-methylselenocysteine was the major Se-containing component, along with lesser amounts of Se-methylselenocysteine. Trace quantities of dimethyl selenide and allyl methyl selenide are found in human breath after consuming raw garlic. Indeed, organoselenium compounds have a terrible smell.
Sources: en.wikipedia.org
=== ATLAS and P-body === ATLAS and P-body (known as Blue and Orange to GLaDOS) are player characters in the co-op campaign of Portal 2. They are two robots that cannot speak and can only produce grunts, which are voiced by Dee Bradley Baker. They are equipped with their own portal guns which bears the colour of its user (blue and purple for ATLAS, yellow and red for P-body). Atlas and P-Body are described as masculine and feminine, respectively, as stated by Chet Faliszek in an interview. During the campaign, GLaDOS calls them Blue and Orange, respectively, and constantly tries to ruin their relationship by awarding one and ignoring the other. GLaDOS sends ATLAS and P-body into four areas to access data discs. Once done, they are blown up, as GLaDOS claims it is the only way they can be retrieved from these areas. Later, GLaDOS commands them to retrieve a certain "surprise" in an area. They go in search, only to find hundreds of thousands of other test subjects in suspended animation. After the co-op campaign is finished, GLaDOS quotes that they saved science. ATLAS and P-body begin to celebrate, only to be promptly blown up by GLaDOS. In the DLC campaign "Peer Review", ATLAS and P-body are reactivated by GLaDOS one week after the original co-op campaign, during which GLaDOS has already wiped out all of the found test subjects in her attempts to turn them into "killing machines". The two robots are sent to find a saboteur that has taken control of a prototype central core and is causing problems in the facility.
==== Italy, South Leigh and Prague ==== The following year, in April 1947, the Thomases travelled to Italy, after Thomas had been awarded a Society of Authors scholarship. They stayed first in villas near Rapallo and then Florence, before moving to a hotel in Rio Marina on the island of Elba. On their return, Thomas and family moved, in September 1947, into the Manor House in South Leigh, just west of Oxford, purchased and rented to Thomas for £1 per week by Margaret Taylor. He continued with his work for the BBC, completed a number of film scripts and worked further on his ideas for Under Milk Wood, including a discussion in late 1947 of The Village of the Mad (as the play was then called) with the BBC producer Philip Burton. He later recalled that, during the meeting, Thomas had discussed his ideas for having a blind narrator, an organist who played for a dog and two lovers who wrote to each other every day but never met. In March 1949 Thomas travelled to Prague. He had been invited by the Czech government to attend the inauguration of the Czechoslovak Writers' Union. Jiřina Hauková, who had previously published translations of some of Thomas's poems, was his guide and interpreter. In her memoir, Hauková recalls that at a party in Prague, Thomas "narrated the first version of his radio play Under Milk Wood." She describes how he outlined the plot about a town that was declared insane, mentioning the organist who played for sheep and goats and the baker with two wives.
The constitutional status of a union territory is similar to a state under the perennial president's rule per Article 356 subject to specific exemptions to a few union territories with legislative assembly. As Per Article 240 (1), supreme power is accorded to the president in regulating the affairs of all the union territories except Chandigarh, NCT and Puducherry, including powers to override the laws made by Parliament and the constitution of India. Article 240(2) allows implementing tax haven laws in these union territories to attract foreign capital and investments into India instead of depending on foreign tax haven countries. The difference between states as listed in the First Schedule of the constitution and union territories with legislative assembly is that states were given autonomous powers as provided in the constitution without any possible interference by the parliament whereas UTs with legislative assembly (Part VIII) has similar powers but parliament is empowered to modify or repeal or suspend the laws made by a union territory (ultimate authority by the parliament unlike the independent nature of the states). Three of the union territories have representation in the upper house of the Indian Parliament, the Rajya Sabha: Delhi, Jammu and Kashmir, and Puducherry. Puducherry, Jammu and Kashmir and NCT of Delhi are the only three union territories that are exceptional among union territories in that each has its own locally elected legislative assembly and have a chief minister.
Sources: en.wikipedia.org
Mahathir also strengthened political and economic cooperation with China, whilst maintaining diplomatic ambivalence on security issues to avoid escalating territorial disputes in the South China Sea. He openly criticised China's involvement in Malaysia's communist insurgency, but downplayed any military threat from China after the Cold War ended. In 1985, Mahathir visited China for the first time as prime minister, where he met Chinese leader Deng Xiaoping, establishing a new level of trust that laid the foundation for Malaysia-China relations and set the stage for decades of economic and diplomatic growth. Later, he visited China again in 1993, 1994, 1996, 1999, and twice in 2001. In the early 1990s, Mahathir played a key role in engaging China with ASEAN despite South China Sea disputes, particularly in the post-Tiananmen and post-Cold War contexts, paving the way for then Chinese Foreign Minister Qian Qichen to attend the ASEAN meeting's opening ceremony in July 1991 as a guest of the Malaysian government, and eventually leading to China's upgrade to ASEAN's dialogue partner in 1996. Amidst the Asian financial crisis, Mahathir also led several large delegations to China and Russia to seek regional economic cooperation. Besides that, Mahathir also had significant interactions with Taiwan, especially during the 1980s and 1990s, when economic ties between the two sides were at their strongest despite the lack of formal diplomatic relations.
==== Delivery methods ==== Honokiol is most commonly taken orally. There are a number of supplements available containing honokiol. Magnolia tea made from the bark of the tree is also a common delivery method of honokiol. Both Native American and Japanese medicine use tea gargles to treat toothaches and sore throats. Because honokiol is highly hydrophobic it must be dissolved in a lipid for many delivery methods. In many current animal studies the compound is dissolved in a lipid emollient and delivered through intraperitoneal injection. There is ongoing work developing liposomal emulsions for IV delivery.
Lorcaserin is a selective 5-HT2C receptor agonist, and in vitro testing of the drug showed reasonable selectivity for 5-HT2C over other related targets. 5-HT2C receptors are located almost exclusively in the brain, and can be found in the choroid plexus, cortex, hippocampus, cerebellum, amygdala, thalamus, and hypothalamus. The activation of 5-HT2C receptors in the hypothalamus is supposed to activate proopiomelanocortin (POMC) production and consequently promote weight loss through satiety. This hypothesis is supported by clinical trials and other studies. While it is generally thought that 5-HT2C receptors help to regulate appetite as well as mood, and endocrine secretion, the exact mechanism of appetite regulation was not known as of 2005. Lorcaserin has shown 100x selectivity for 5-HT2C versus the closely related 5-HT2B receptor, and 17x selectivity over the 5-HT2A receptor.
Sources: en.wikipedia.org
It is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, often abbreviated AEDG. The molecule is linear and contains no modified residues, so it is fully described by its sequence.
The compound came out of work on epithalamin, a peptide preparation derived from pineal tissue, conducted largely in Russian laboratories. Later studies in other countries examined it mainly in cell cultures and animal models.
The tetrapeptide sequence is a synthetic construct rather than a described circulating peptide. It was derived by analogy to peptide fractions obtained from tissue extracts, not isolated from blood or tissue as such.
It is a four-amino-acid peptide built from alanine, glutamate, aspartate and glycine in that order. Its formula is C14H22N4O9, and it is made by chemical synthesis rather than extracted from tissue. The synthetic peptide is a single defined molecule, unlike the pineal extracts it is often compared with.